Hybrid functional materials and their derivatives are propelling a technological revolution in chemistry, materials science, and other disciplines. The performance of hybrid materials touches many fundamental aspects of energy conversion and storage, sustainable environment, and life sciences. Based on their rich chemistry, diverse metal phosphonates and their derivatives can be synthesized. These materials manifest various structures and enable new functionalities, which are hardly attainable in simple mixtures or other multicomponent materials. Here, we highlight and discuss the fascinating materials design innovations that organophosphonates can enable, with an eye on energy, environment, and biological applications.